Coulomb excitation in intermediate-energy collisions

Abstract

We study the interplay between retardation and Coulomb recoil in the theory of Coulomb excitation of heavy ions at bombarding energies around 100 MeV/nucleon. A semiclassical calculation with relativistically corrected trajectories and a full expansion of the electromagnetic propagator is performed. At these energies Coulomb excitation of giant resonances become dominant and the cross sections for it are very large, especially at grazing collisions. A comparison with the nonrelativistic and with the relativistic calculations is made, showing that in intermediate-energy collisions neither of those reproduce the correct values of the cross sections.